1. Field of the Invention
The present invention is a new type of pet door that includes a frame that mounts in an opening created for this purpose in a door or wall 18 of a building. A flap is hinged at the top of the frame on either side of the frame so that the flaps open by swinging away from the frame. Each of the flaps is provided with an outwardly angled flange that extends around three sides of the flap. This flange allows a pet to nuzzle open the flap located on the side of the frame from which the pet is approaching. Once the pet has opened the first flap, the pet opens the opposite second flap by pushing against it.
2. Description of the Related Art
Various types of pet doors are available in the marketplace. One popular type employs a double frame rubber door arrangement that hinges at the top and is opened by a pet pushing on the door. When the pet pushes on the door one frame swings outward, or alternately, the other frame swings inward, depending on the direction the animal is traveling as it passes through the door. After the pet passes through the door, the door and the double frames hang downward to form a barrier to water and air passing there through. The issue with this kind of door is that wind blows it open or air pressure in the house blows it open, thus causing loss of heat or cooling.
Another type of pet door has two separate doors located side by side so that a pet pushes against one door to enter and pushes against the other door to exit. Additionally, this type of pet door requires the pet to learn which door to push against when entering and which door to push against when exiting, adding to the difficulty of teaching the pet how to operate this type of door. This type of pet door also has the disadvantage of requiring a larger total opening than for those pet doors where the pet enters and exits through a single door opening.
Other types of dog doors are hinged on the side instead of at the top and have springs to close the door instead of allowing the door to close under the influence of gravity. U.S. Pat. No. 3,874,118 is one such dog door. This patent teaches a flange on only one side of the door. This spring loaded door will often startle the pet as the pet attempts to pass through them, causing the pet to recoil. When the pet recoils, the pet's head, tail or other appendage can become trapped between the door and the door frame, further scaring the animal and potentially causing the animal to react in such a manner as to injury or even possibly kill the pet.
The present invention addresses these problems by providing a dog door with a frame that installs in a single door opening and employs dual flaps hinged at the top and located on either side of a frame to thereby prevent unwanted air or moisture from passing through the frame. Each flap is provided with an outwardly angled flange that extends around three sides of the flap, i.e. the right and left sides and the bottom of the flap. This flange allows a pet to instinctively nuzzle open the flap located on the side of the frame from which the pet is approaching. Once the pet has opened the first flap, the pet opens the opposite second flap by pushing against it. The flanges on the flaps allow the animal to open the doors in a more natural way by nuzzling the doors open and also prevent an animal from being trapped between one of the flaps and the frame. An additional advantage to this design is that wind blowing inward pushes against the outside flap 12 and helps seal the door. Likewise, air pressure blowing outward from the building pushes against the flap 12 and helps seal the door.